The trial was closed to foreign news organizations, hindering independent confirmation of developments.

Australian consular officials were allowed in the Shanghai courtroom for the bribery phase of the case, but were barred from witnessing the theft portion.

Hu is accused of receiving two bribes: one for 1 million yuan ($146,490) and another for 5.3 million yuan ($790,000). The Australian Department of Foreign Affairs and Trade said he "made some admissions concerning these amounts," but did not elaborate.

The Chinese government initially accused the four of stealing state secrets when they were first detained, but the charges were reduced to theft of commercial secrets several months ago.

Hu and the others were detained in July. China says the four bribed executives from 16 of the nation's major steel mills to obtain industry information.

In China, obtaining commercial secrets carries a maximum penalty of seven years in prison.

Rio Tinto has called the allegations surprising and said it was not aware of any evidence.

The detentions took place about a month after Rio Tinto broke off an investment deal with China state-owned Chinalco, a resources company, that was worth more than $19 billion.

The deal with Chinalco was signed in February 2009 and was awaiting a review by Australia's foreign investment board.

The deal soured as opposition party members in Australia ratcheted up their disapproval, saying it would put Australian resources at strategic risk.

Others saw the deal as an alliance that would further link resource-rich Australia with the commodities-hungry Chinese market.